Friedrich sauer and carl hentzschel



(No Model.)

V P. SAU ER- 8v O.' HYE;NTZSOHEL,.

ELECTRIC ALARM.

Patented Feb. 6, 1894.

UNITED STATES PATENT" OFFICE.

FRIEDRICH SAUER AND CARL HENTZSCHEL, OF BERLIN, GERMANY.

ELECTRIC ALARM.

SPECIFICATION forming part of Letters Patent No. 514,202, dated February 6, 1894. Application filed July 8, 1893- Serial No. 4791938- (No model.)

T0 at whom it may concern:

Be it known that we, FRIEDRICH SAUER. and CARL HENTZSOHEL, both subjects of the King of Prussia, and residents of Berlin, in theIKingdom of Prussia, German Empire, have invented a certain new and useful Improved Electric Alarm, of which the following is a full, clear, and exact description.

The present invention consists of an alarm device for doors, windows, safes and similar purposes and it is constructed to' give an alarm as soon as the bolt ot' the lock is withdrawn to open the door, window, safe, the.

The device consists of a spring pressed 1ever normally kept out of contact with the two poles of an electric circuit by the bolt of the look when the latter isin position in the bolt nab or striking plate.

In order to make the invention more clearly intelligible reference is had to the accompanying drawings, in which similar letters denote similar parts throughout the several views. g

Figure 1 is a side elevation of the device with the circuit closed. Fig. 2 is a similar elevation showing the circuit broken and Fig. 3 is a plan of the device.

To the angle plate a, pivotally mounted at f in bearings e e is attached a double arm lever A having its upper arm 9 held against the poles c c by a spring I), when the lower arm g is not in contact with the bolt of the lock. The points of contact 0 c are mounted in a block d having finger ring 11 and detachably mounted between the guide angles k lg. The circuit wires may be connected to the points of contact 0 c in the usual manner as shown at Fig. 2.

The apparatus is mounted behind the striking plate of the lock in such manner that the lower arm g of the lever A will contact with the bolt 0 of the look when the said bolt is in the bolt nab or striking plate, or in other words when the lock is closed, and thus the upper arm g of the said lever A will be withheld from the contacts 0 0' against the pressure of the spring b.

The operation of the apparatus is obvious, viz as soon as the bolt is withdrawn from the striking plate the lever A will be released and close the circuit at c c and give the alarm.

During the daytime or when not required the apparatus may be placed out of action by removing the detachable block at from its position between the guides in k.

We claim as our invention- The combination of the double arm lever A pivotally mounted at f and having spring I) operating to form contact between the upper arm 9 of said lever A and circuit poles c c and lower arm g normally depressed by the bolt of the lock and the block 0 having contacts c c and detachably mounted in guides It is substantially as described.

In testimony whereof we have hereunto set our hands, at Berlin, Germany, this 15th day of June, 1893, in the presence of two subscribing witnesses.

FRIEDRICH SAUER. CARL HENTZSCHEL.

Witnesses:

EMIL SAVOR, H. HEINIOKE. 

